The present invention relates generally to multi-tools, which typically are pliers-based hand tools having one or more tools stored in one or both of the handles of the pliers. Other pliers-like devices may be the basis for the present multi-tool, such as scissors or wire cutters. The common element among pliers, scissors and wire cutters is that each includes a pair of opposing jaws operated by a pair of opposing handles. When the handles of such a jaw/handle combination store one or more tools, the entire device is a multi-tool.
The tools may be stored in a pocket formed in the handle. Examples of tools found in multi-tool handles include knife blades, can openers, screwdrivers, files, scissors, and saw blades. These tools fold into and out of the handle of the multi-tool, similar to a knife blade folding into and out of a pocket knife, and thus may be referred to in this document as foldable tools. Multi-tools often include other tools that do not fold, such as a ruler stamped into an exposed surface of one or both handles of the multi-tool.
Examples of prior multi-tools are found in U.S. Pat. Nos. 1,561,993, 3,798,687, 4,238,862, 4,563,833, 4,744,722, 4,888,869, 4,942,637, 5,029,355, 5,142,721, 5,212,844, and 5,267,366, incorporated herein by reference. Two of these U.S. Pat. Nos. 4,238,862 and 5,029,355, disclose attempts to provide a locking mechanism for pliers as part of a multi-tool. In both of these prior multitools, the locking mechanism must be stored in a non-operating position, requiring the user of the multi-tool to deploy the locking mechanism from its non-operating position to its operating position before the pliers can be locked about an object. The user then needs to return the locking mechanism to its non-operating position after use. Deploying and returning the locking mechanism unduly complicates use of the locking aspect of the pliers of these prior multi-tools.
U.S. Pat. No. 4,238,862 also discloses a multi-tool in which the foldable tools are lockable in an extended, open position. The tool is locked when a tab on a locking spring aligns with a matching slot in the tool. The locking spring is formed as part of the web that interconnects opposing walls of the handle. Unlocking the tool from its locked, open position requires that another of the foldable tools stored in the same handle be unfolded partially to release the locking spring from the slot in the locked tool. The difficulty of unlocking a locked tool in this prior device has been found to be a drawback of the device.
U.S. Pat. No. 5,142,721 discloses an alternative locking mechanism to prevent a tool from folding from its open position to its closed position, as shown in FIG. 8 of that patent. The handles of the disclosed multi-tool may be pressed toward each other to a pressed-together position, and locked in that position by retracting the jaws into the handles. The tool-receiving pocket in each of the handles faces toward the other handle, and is obstructed by the other handle when the handles are in the pressed-together position. This prevents a foldable tool already in its open position from being returned to its pocket until the handles are released from the pressed-together position. It thus offers a type of locking mechanism for the various foldable tools in a multi-tool.
This locking mechanism is simple in practice and often effective. For certain uses, however, this prior art locking mechanism does not provide a sufficiently positive lock for the tool being used because the tool is able to pivot somewhat within its open position before it contacts the tools of the opposing handle. This results in a significant amount of free play in the tool when the tool is in its open position. Many tools, such as screwdriver tool blades, are much easier to use when positively locked in an open position, with little, if any, free play.
In the present multi-tool, the free play just described is eliminated by a positive lock provided by an outwardly extending shoulder formed on the foldable tools, adjacent the end of the tool and adjacent the pin on which the tool pivots. The shoulder interacts with a flange formed on the opposing handle. The flange exerts a concentrated force against the shoulder of the foldable tool when the handles are in the pressed-together position, and limits the amount of free play when the tool is in this locked position. A clasp is connected to one of the handles, and pivotable into engagement with the other of the handles to lock the handles in the pressed-together position, if desired.
At least one of the handles of the present multi-tool may be formed to include two oppositely facing pockets in which tools may be stored. For example, one of the pockets in the preferred embodiment stores a foldable knife blade, and the other stores an adjustment mechanism used in locking the multi-tool""s plier jaws about an object. When viewed along the handles, approximately perpendicular to the longitudinal axis of the handles, at least one of the handles may be formed so that its body has a cross section that is S-shaped. The other handle may be U-shaped or S-shaped, and preferably includes at least one pocket that faces toward the S-shaped handle so that the pressed-together locking position of the handles may be used to lock open foldable tools stored in the other handle.
Forming oppositely facing pockets in a single handle allows at least one foldable tool to be exposed regardless of the orientation of the tool-receiving handle relative to the opposing handle. Thus, the exposed tool may be opened and closed even if the plier jaws are clamped about an object. The exposed tool also may be a foldable tool, while the tool in the oppositely facing pocket may be a non-foldable tool. A further alternative made possible by the oppositely facing pockets of the present multi-tool is that the exposed tool may be opened and closed while another foldable tool is locked in an open position by the pressed-together locking position of the handles, just described.
In the prior art multi-tools, the combination of easily locked foldable tools and exposed foldable tools was not possible. In some prior multi-tools, there is no exposed foldable tool. In other prior multi-tools, the handles need to be placed in a non-operating position if a foldable tool is to be exposed. In yet other prior multi-tools, none of the pockets in the handles allows a pressed-together locking function for the foldable tools. The present multi-tool offers an effective solution for these prior art problems, a solution not previously available.
A further improvement found in the preferred embodiment of the present multi-tool is a post mounted on at least one of the foldable tools. The post is exposed for engagement by a human hand to facilitate one-handed deployment of the knife blade from its closed position to its open position. This is particularly useful when the post is mounted on the exposed tool in one of the oppositely facing pockets just described.
The pocket in which the foldable knife blade is stored also preferably is formed to include a leaf spring that extends into the pocket, and that locks the knife blade in an open position by blocking at least a portion of the tool-receiving pocket. This leaf spring is exposed for engagement by a human hand so that the leaf spring may be pushed back out of the pocket to allow the knife blade to return to its closed position. All of the foldable tools of the present multi-tool therefore are provided with a lock to hold the tools firmly in an open position.
It is an object of the present invention to provide a multi-tool in which at least one foldable tool is usable despite the orientation of the handles of the multi-tool.
It is a further object of the invention to provide a multi-tool in which foldable tools may be locked in a positive-locked open position by locking the handles in a pressed-together position.
Yet another object of the invention is to provide a multi-tool in which a foldable tool is locked in its open position by a leaf spring that extends into a tool-receiving pocket.
Yet another object of the invention is to provide a multi-tool in which a foldable tool is easily deployable in one-handed use.
Additional objects and advantages of the present invention will be understood more readily after a consideration of the drawings and the Detailed Description of the Preferred Embodiment.